Abstract: Disclosed is a tandem-type image forming system performing single-sided printing and double-sided printing on a sheet, the image forming system including: a first image forming apparatus; and a second image forming apparatus connected with the first image forming apparatus in series, wherein when the single-sided printing is performed, either the first image forming apparatus or the second image forming apparatus performs printing on a sheet, and when the double-sided printing is performed, both the first image forming apparatus and the second image forming apparatus performs the printing on a sheet, the image forming system further including: a control section which controls a sheet-passing image forming apparatus which is either the first image forming apparatus or the second image forming apparatus, and does not perform the printing but performs sheet-passing in the single-sided printing.

Abstract: An image forming apparatus includes a patch image generation unit which generates a patch image for image density detection disposed between toner images, and a patch density sensor which detects a density of the patch image. In order to prevent the output quality of a printed image from varying with the type of paper use, a correction unit performs correction processing to match a detected density and a target density by comparing the detected density of the patch image detected by the patch density sensor and the target density of the patch image which is set in advance, a toner deposit control unit controls a toner deposit when the image forming unit forms an image based upon image data and when the patch image generation unit generates the patch image, and a paper interval control unit controls an interval between consecutive papers.

Abstract: Disclosed in an image forming apparatus including a conveyance section to convey a paper, a first fixing device to fix a toner on the paper by heat fixing, a first cooling device to cool the paper in which the toner is fixed, a second fixing device to fix the toner on the paper by heat fixing, a second cooling device to cool the paper in which the toner is fixed, a conveyance path switching section to switch a conveyance path of the paper between a first conveyance path and a second conveyance path and a control section to control so as to carry out cooling by operating the second cooling device and not operating the first cooling device when the paper is to be conveyed to the first conveyance path and so as to carry out cooling by operating the first cooling device when the paper is to be conveyed to the second conveyance path.

Abstract: An image forming apparatus having: a plurality of image forming sections each of which forms images of respective colors; an intermediate transfer belt; and a control section which executes a color registration correction process and a deviation correction process, wherein the color correction process includes: forming test images on the intermediate transfer belt by the plurality of image forming sections; measuring the test images thereafter; and correcting image forming positions of the image forming sections in response to the measurement results; and wherein the deviation correction process includes: detecting a deviation of the intermediate transfer belt; and correcting the detected deviation, and wherein, when an amount of correction in the deviation correction process exceeds a predetermined level during the execution of the color registration correction process, the control section executes the color registration correction process again.

Abstract: Disclosed is an image forming apparatus including an image forming unit which performs image forming on a paper, an image carrier on which a toner image is formed by the image forming unit, a patch image generation unit which generates a patch image for image density detection so as to be disposed between toner images, a patch density sensor which detects a density of the patch image, a correction unit which performs correction processing to match a detected density and an aimed density by comparing the detected density of the patch image detected by the patch density sensor and the aimed density of the patch image which is set in advance, a toner deposit control unit which controls a toner deposit when the image forming unit performs image forming, and a paper interval control unit which control an interval between consecutive papers.

Abstract: Disclosed is a tandem-type image forming system performing single-sided printing and double-sided printing on a sheet, the image forming system including: a first image forming apparatus; and a second image forming apparatus connected with the first image forming apparatus in series, wherein when the single-sided printing is performed, either the first image forming apparatus or the second image forming apparatus performs printing on a sheet, and when the double-sided printing is performed, both the first image forming apparatus and the second image forming apparatus performs the printing on a sheet, the image forming system further including: a control section which controls a sheet-passing image forming apparatus which is either the first image forming apparatus or the second image forming apparatus, and does not perform the printing but performs sheet-passing in the single-sided printing.

Abstract: A bias correction is carried out before a color registration correction is carried out so as to stabilize the running state of an intermediate transfer belt, thereafter the bias correction ceases and the color registration correction is carried out.

Abstract: Bias correction control of an intermediate transfer belt 21 on which an image of each color formed on a surface of a photoconductive body 31 is transferred, and a second transfer belt 24 in pressure contact with the intermediate transfer belt 21 to transfer a toner image onto a recording sheet by passing the recording sheet between the intermediate transfer belt 21. Contents of the bias correction control (an amount of correction control and a cycle of correction control) can be changed in accordance with states of the belts i.e. whether the intermediate transfer belt 21 and the second transfer belt 24 are in a pressure contact state or a separate state.

Abstract: An image forming apparatus includes: a rotating belt which rotates around a roller; a drive section which rotates the belt; a detection section which detects a position of the belt in a width direction; a moving section which moves the belt in the width direction; a control section which corrects a deviation of the belt by controlling the moving section. The control section conducts a preparatory operation in which the control section changes an amount of control to be given to the moving section under the condition where the belt is rotated to obtain a correction data showing a relation between the amount of control and a change of a position of the belt in the width direction detected by the detection section, stores the correction data in a memory section, and then corrects the deviation based on the correction data stored in the memory section.

Abstract: The present invention realizes an image forming system wherein an efficient cleaning of plural fixing apparatuses by using a blank sheet is attained, the system includes: an image forming section; a sheet feeding apparatus; a plurality of fixing apparatuses; a temperature control section controlling the temperature of the fixing apparatuses; a sheet retention determination section determining whether there is a sheet retained in any of the fixing apparatuses during a jam; and a control section controlling cleaning of the fixing apparatuses by a blank sheet fed from the sheet feeding apparatus, wherein the control section carries out cleaning of the fixing apparatus in which it has been determined that a sheet is retained based on input from the sheet retention determination section, when the temperature of the fixing apparatus has been determined to have reached a prescribed temperature based on input from the temperature control section.

Abstract: Disclosed in an image forming apparatus including a conveyance section to convey a paper, a first fixing device to fix a toner on the paper by heat fixing, a first cooling device to cool the paper in which the toner is fixed, a second fixing device to fix the toner on the paper by heat fixing, a second cooling device to cool the paper in which the toner is fixed, a conveyance path switching section to switch a conveyance path of the paper between a first conveyance path and a second conveyance path and a control section to control so as to carry out cooling by operating the second cooling device and not operating the first cooling device when the paper is to be conveyed to the first conveyance path and so as to carry out cooling by operating the first cooling device when the paper is to be conveyed to the second conveyance path.

Abstract: An image forming apparatus having: a reading section that reads out an image of an original document placed on a document table; a storage section that stores image data obtained by reading out the image by the reading section; a sheet feeding section including a sheet feeding tray and an attachment detection sensor that detects whether or not the sheet feeding tray has been attached; and a control section that executes reading out of the image in a mode in which the image is read while the reading section scans the image of the original document placed on the document table, wherein the control section, when the attachment or detachment of the tray is detected during execution in the mode, suspends the reading out of the image, deletes the image data obtained from the original document image whose reading was suspended, and moves the scanning unit to a home position.

Abstract: An image forming apparatus which forms an image on a sheet, includes a controller which executes a cleaning mode in which the controller conveys the sheet from a sheet feed tray to a fixing device without forming a toner image on the sheet, removes toner that has been adhered to a fixing member to clean. In case the cleaning mode is executed, the controller controls a releasing section to release pressure contact of a pressing member before a leading edge of the sheet in a sheet conveyance direction reaches a nip portion between the fixing member and the pressing member, and to bring the pressing member into pressure contact with the fixing member after the leading edge of the sheet has passed through the nip portion.

Abstract: An image forming apparatus, including an image forming section which conducts image formation on a sheet based on an image data, a tray which accommodates the sheets to be supplied to the image forming section, a humidity detecting unit which detects humidity inside the tray, a dehumidifying device which conducts dehumidification inside the tray; and a control section which controls the image forming section to prohibit image formation when the humidity inside the tray is higher than a predetermined value, the control section further controls the dehumidifying device to conduct the dehumidification inside the tray when the humidity inside the tray is equal to or lower than the predetermined value, and the control section still further controls the image forming section to conduct the image formation on the when the humidity inside the tray has been equal to or lower than the predetermined value.

Abstract: An image forming apparatus, including an image forming section which forms image on a recording sheet based on image data, plural trays which accommodate the sheets to be supplied to the image forming section, a humidity detecting unit which detects humidity inside the paper tray, a dehumidifying device which dehumidify inside the paper tray, and a control section which controls the dehumidifying device and management of jobs, and controls the image forming section to execute the jobs, wherein if the humidity inside the paper tray to be used for a first priority job is higher than a predetermined value, the control section suspends execution of the first priority job, and the control section controls the image forming section to execute a reserved job which is executable from among reserved jobs with low priority order, before executing the first priority job.

Abstract: Bias correction control of an intermediate transfer belt 21 on which an image of each color formed on a surface of a photoconductive body 31 is transferred, and a second transfer belt 24 in pressure contact with the intermediate transfer belt 21 to transfer a toner image onto a recording sheet by passing the recording sheet between the intermediate transfer belt 21. Contents of the bias correction control (an amount of correction control and a cycle of correction control) can be changed in accordance with states of the belts i.e. whether the intermediate transfer belt 21 and the second transfer belt 24 are in a pressure contact state or a separate state.

Abstract: There is described an image forming apparatus comprising a tray that outputs information by which various kinds of fixed form sized of recording mediums can be discriminated and a controller to acquire a approximate size of a recording medium having an unfixed form size by conducting an operation for detecting a fixed form size of the recording medium by referring to the information if the recording medium having the unfixed form size is stacked on the tray, wherein, according to the approximate size, the controller controls an operation for displaying information corresponding to unfixed form size or sizes registered in advance.

Abstract: An image forming apparatus includes: a rotating belt which rotates around a roller; a drive section which rotates the belt; a detection section which detects a position of the belt in a width direction; a moving section which moves the belt in the width direction; a control section which corrects a deviation of the belt by controlling the moving section. The control section conducts a preparatory operation in which the control section changes an amount of control to be given to the moving section under the condition where the belt is rotated to obtain a correction data showing a relation between the amount of control and a change of a position of the belt in the width direction detected by the detection section, stores the correction data in a memory section, and then corrects the deviation based on the correction data stored in the memory section.

Abstract: The bias correction is carried out before the color registration correction is carried out so as to stabilize the running state of the intermediate transfer belt, thereafter the bias correction ceases and the color registration correction is carried out.

Abstract: An image forming apparatus having: a plurality of image forming sections each of which forms images of respective colors; an intermediate transfer belt; and a control section which executes a color registration correction process and a deviation correction process, wherein the color correction process includes: forming test images on the intermediate transfer belt by the plurality of image forming sections; measuring the test images thereafter; and correcting image forming positions of the image forming sections in response to the measurement results; and wherein the deviation correction process includes: detecting a deviation of the intermediate transfer belt; and correcting the detected deviation, and wherein, when an amount of correction in the deviation correction process exceeds a predetermined level during the execution of the color registration correction process, the control section executes the color registration correction process again.